When applying the AOE at subcritical conditions (subcritical
water extraction) the possibility of triglyceride hydrolysis to free
fatty acids and glycerol also arises. Such a result would cause a
decrease in oil quality, since more intensive down-stream processing
(refining) would be required for removal of these compounds.
Also, another factor which diminishes oil quality is the hydrothermal
degradation of naturally present vitamins and antioxidants e.g.
phytosterols and tocopherols